Interference limits the throughput in cellular communication systems. At receiving end, receivers try to reduce the impact of the interference. One approach used to reduce the impact of interference is channel cancellation in which channels with known interfering symbols are removed from the received signal prior to processing the unknown channels. Here, symbols on other channels may carry important information to the UE, but for other parts or purposes, and it is therefore desirable to remove them from the signal during reception to improve reception performance. The cancellation may for example reduce inter symbol interference. These unknown channels can consist of both control channels and data channels, where typically the latter will benefit the most from interference cancellation due to their typically higher Signal-to-Interference-and-Noise-Ratio (SINR) requirements.
The channels with known symbols are typically channels that repeatedly transmit the same symbols. The sequence of known symbols may be known a priori, e.g. from system information or specifications and for example some synchronisation channels, or be determined by demodulating and decoding the symbols. The latter case is often referred to as successive interference cancellation (SIC). For the case that the symbols are always known a priori, performing interference channel cancellation is a straightforward task and traditionally used in the field of technology. However, if this is not always the case, improper cancelling, i.e. cancelling wrong symbols, may decrease performance.